ON THE LABORATORY OF THE MARINE BIOLOGICAL ASSOCIATION. 357 



anatomy of Polych^t worms, and to determine the amount of value to be 

 attached to chset^ and parapodia of homologous segments as a means of 

 classification. I found, however, that I must begin by identifying the 

 difi'erent forms occurring at Plymouth, as very little work had been done 

 there on Polychsets up to that time. Seeing that every Polychaet has, 

 on the average, a good many more than half a dozen names, and that 

 each name belongs to about half a dozen different Polycheets, this is no 

 very easy task, and it has occupied me, on and off, since my return from 

 Plymouth in the Zoological Laboratory of University College, London, 

 and I am afraid is not yet complete. I obtained, altogether, over a 

 hundred different species, some of them found, I believe, for the first time 

 on our coast, and a few which seem to be new altogether. With regard 

 to the collection of them, I have to thank my fellow-workers in the 

 laboratory, and especially Mr. Garstang, for much help given me. I 

 must also thank Mr. Cunningham for notes and drawings of some of 

 the Plymouth Polychaets found there up to that time, which he kindly 

 placed at my disposal. With regard to the naming of them, I have 

 received a good deal of assistance from an incomplete and as yet 

 unpublished ' Synonymous List of Polychget Worms,' by Professor 

 Haddon, which he has kindly put into my hands for revision and 

 completion. 



The most interesting of the new forms obtained is a small Eunicid, 

 resembling the genus Ophryotrocha of Claparede and Metschnikoff (' Z. f, 

 w. Z.' XIX. p. 184, PI. XIII. fig. 2) in having the larval ciliated bands 

 persistent in the adult. The shape of the jaws and parapodia (which I 

 propose to figure in giving a full account of this small worm elsewhere), 

 the possession of two pairs of prostomial tentacles instead of only one, and 

 these both provided with stiff hairs not only in the young stages but in 

 the adult, seem to me, however, to mark it off as a distinct genus, 

 although certainly more nearly allied to Ophryotrocha than to any other 

 known Annelid. There is a ciliated band on the prostomium, and one on 

 each of the following segments. All the segments after the first two 

 (and the last two or three in small specimens) have well-developed para- 

 podia, each consisting of a chaetigerous lobe containing both simple and 

 compound chtetiB, and a small cirrus. In the body-cavity and in the 

 parapodia of most of the specimens eggs are to be found, which, curiously 

 enough, like those of Ophryotroclia, are generally double, consisting, 

 namely, of a large granular part, of a yellowish-brown colour, containing 

 (in this case, but evidently not in the eggs of Ophryotroclia) the nucleus, 

 and a smaller colourless part (containing the nucleus in eggs of Ophryo- 

 troclia) which stains very deeply with carmine. Whether this smaller 

 part represents a polar body or not remains to be determined. Sections 

 show that at least one pair of excretory organs is present in the shape 

 of small tubes blocked up by yellow concretions lying in the second 

 and third segments and (?) opening at the side of the second to the 

 exterior. 



The only other form amongst those I have as yet examined which may 

 rank as a new genus is a member of the family Ampharetea, differing from 

 Samytha and Amage especially in having a large number of segments (at 

 least thirty-seven) with uncinigerous pinnules behind those with bundles 

 of capillary setee. It would either form a new genus with the Samytha 

 pallescens of Theel (' Kongl. Sv. Vet. Ak. Handlingar,' Bd. XVI.), which 

 he places doubtfully as a Samytha, or the genus Samytha must be enlarged 



